Reducing crack formation in low-carbon rolled bar produced from continuous-cast blank

The δ→γ phase transformation in the steel was studied in detail, and the relationship between δ→γ phase transformation and the crack formation in continuous casting slabs was discussed as well. The results indicate that the micropores are formed at the positions where δ-phase transformation terminates during the δ→γ phase transformation for low-carbon non-peritectic steel. The micropores will also be formed at the positions where the peritectic reaction of the steel terminates, then the pores are remained on the grain boundary of γ-phase when γ-phase becomes granulated. The micropores distributing on the grain boundary of γ-phase is one of the results for the crack formation of continuous casting slabs and the obvious plasticity decrease of δ-phase zone in the steel. The theoretical analysis results are basically consistent with the experimental results.

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Development of Low Carbon Continuous Cast Steels for Bar and Wire Rod and Its Properties

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.72.11_1693 ◽

1986 ◽

Vol 72 (11) ◽

pp. 1693-1700

Author(s):

Kiyomi TAGUCHI ◽

Eihachiro SUNAMI ◽

Katsuhiko NISHIKAWA ◽

Katsundo TEZUKA ◽

Toyoaki EGUCHI ◽

...

Keyword(s):

Low Carbon ◽

Continuous Cast ◽

Wire Rod ◽

Cast Steels

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Prediction and control of subsurface hooks in continuous cast ultra-low-carbon steel slabs

Ironmaking & Steelmaking ◽

10.1179/174328108x369071 ◽

2009 ◽

Vol 36 (1) ◽

pp. 39-49 ◽

Cited By ~ 19

Author(s):

G.-G. Lee ◽

H.-J. Shin ◽

S.-H. Kim ◽

S.-K. Kim ◽

W.-Y. Choi ◽

...

Keyword(s):

Carbon Steel ◽

Low Carbon Steel ◽

Low Carbon ◽

Continuous Cast ◽

Prediction And Control ◽

Ultra Low Carbon Steel ◽

Steel Slabs ◽

And Control

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S.E.M.-T.E.M. Image Comparison

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064712 ◽

1971 ◽

Vol 29 ◽

pp. 132-133

Author(s):

G. M. Greene ◽

J. W. Sprys

Keyword(s):

Electron Microscope ◽

Low Carbon Steel ◽

Secondary Emission ◽

Low Carbon ◽

Preparation Time ◽

Actual Surface ◽

Fine Detail ◽

Transmission Electron ◽

Transmission Study ◽

Large Sections

The present study demonstrates that fracture surfaces appear strikingly different when observed in the transmission electron microscope by replication and in the scanning electron microscope by backscattering and secondary emission. It is important to know what form these differences take because of the limitations of each instrument. Replication is useful for study of surfaces too large for insertion into the S.E.M. and for resolution of fine detail at high magnification with the T.E.M. Scanning microscopy reduces sample preparation time and allows large sections of the actual surface to be viewed.In the present investigation various modes of the S.E.M. along with the transmission mode in the T.E.M. were used to study one area of a fatigue surface of a low carbon steel. Following transmission study of a platinum carbon replica in the T.E.M. and S.E.M. the replica was coated with a gold layer approximately 200A° in thickness to improve electron emission.

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Lattice Imaging of Twin, Lath and α/Martensite Boundaries in Duplex Low Carbon Steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078195 ◽

1977 ◽

Vol 35 ◽

pp. 118-119

Author(s):

J. Y. Koo ◽

G. Thomas

Keyword(s):

High Resolution Electron Microscopy ◽

Ferrite Matrix ◽

Carbon Steels ◽

Bright Field Image ◽

Low Carbon ◽

Lattice Imaging ◽

Bright Field ◽

Lattice Image ◽

New Information ◽

Resolution Electron

High resolution electron microscopy has been shown to give new information on defects(1) and phase transformations in solids (2,3). In a continuing program of lattice fringe imaging of alloys, we have applied this technique to the martensitic transformation in steels in order to characterize the atomic environments near twin, lath and αmartensite boundaries. This paper describes current progress in this program.Figures A and B show lattice image and conventional bright field image of the same area of a duplex Fe/2Si/0.1C steel described elsewhere(4). The microstructure consists of internally twinned martensite (M) embedded in a ferrite matrix (F). Use of the 2-beam tilted illumination technique incorporating a twin reflection produced {110} fringes across the microtwins.

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Characterization of carbides in M50NiL

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087343 ◽

1991 ◽

Vol 49 ◽

pp. 606-607

Author(s):

L. S. Lin ◽

K. P. Gumz ◽

A. V. Karg ◽

C. C. Law

Keyword(s):

Temperature Effects ◽

Base Composition ◽

Lattice Parameter ◽

Control Surface ◽

Carbide Formation ◽

Particle Sizes ◽

Low Carbon ◽

Fee Structure ◽

Heat Treated

Carbon and temperature effects on carbide formation in the carburized zone of M50NiL are of great importance because they can be used to control surface properties of bearings. A series of homogeneous alloys (with M50NiL as base composition) containing various levels of carbon in the range of 0.15% to 1.5% (in wt.%) and heat treated at temperatures between 650°C to 1100°C were selected for characterizations. Eleven samples were chosen for carbide characterization and chemical analysis and their identifications are listed in Table 1.Five different carbides consisting of M6C, M2C, M7C3 and M23C6 were found in all eleven samples examined as shown in Table 1. M6C carbides (with least carbon) were found to be the major carbide in low carbon alloys (<0.3% C) and their amounts decreased as the carbon content increased. In sample C (0.3% C), most particles (95%) encountered were M6C carbide with a particle sizes range between 0.05 to 0.25 um. The M6C carbide are enriched in both Mo and Fe and have a fee structure with lattice parameter a=1.105 nm (Figure 1).

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